The present invention relates to a convergence apparatus for use in a color cathode-ray tube in which three electron beams are in-line arranged, particularly a convergence apparatus which is capable of performing several types of dynamic convergences and has a compact construction as a whole.
As well known, in case of an in-line type color cathode-ray tube, various kinds of misconvergence take place resulting from dimensional errors in installation of the electron guns and other parts which are caused in manufacturing the cathode-ray tube, spherical profile of a fluorescent screen of the cathode-ray tube and a pattern of deflection magnetic field. Conventionally, therefore, a pair of E type cores are arranged to oppose each other in the in-line direction (horizontal direction) outside the neck of the cathode-ray tube and the cores are respectively wound with coils around their legs, and a horizontal cycle parabola wave current or a sawtooth wave current and/or a vertical cycle parabola wave current or a sawtooth wave current are supplied to these coils to compensate dynamic misconvergence.
However, such convergence apparatus provides only an electromagnetic force in horizontal or vertical direction or horizontal and vertical directions to the electron beams and cannot therefore meet various types of misconvergences. Since a pair of E type cores are employed, it is disadvantageous in that the construction of the convergence apparatus becomes large as a whole and the manufacturing is complicated due to an increase in the number of parts required.